Acquisitions, Divestitures and Discontinued Operations, Discontinued Operations (Details) - USD ($) $ in Millions			3 Months Ended								12 Months Ended
	Jun. 29, 2018	Feb. 01, 2016	Dec. 31, 2018	Sep. 28, 2018	Jun. 29, 2018	Mar. 30, 2018	Dec. 31, 2017	Sep. 29, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of businesses											$ 42	$ 0	$ 0
Net sales			$ 2,771	$ 2,519	$ 2,583	$ 2,371	$ 2,574	$ 2,293	$ 2,385	$ 2,321	10,244	9,573	9,210
Discontinued Operations [Abstract]
(Loss) income from discontinued operations net of income taxes											205	(76)	91
Liabilities [Abstract]
Current liabilities			0				226				0	226		$ 203
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales												10	59
Vertex Aerospace [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale of business, sale price	$ 540				540
Gain on sale of businesses					237
Gain on sale of businesses, after tax					180
Gain from discontinued operations, before tax	234
Gain from discontinued operations, after tax	177
Net sales											600	1,400	1,300
Discontinued Operations [Abstract]
Goodwill impairment charges								$ 187				187
Vertex Aerospace [Member] | Discontinued Operations [Member]
Assets [Abstract]
Current assets							284					284
Property, plant and equipment, net							13					13
Other intangible assets							7					7
Other assets							2					2
Total assets of discontinued operations							306					306
Liabilities [Abstract]
Accounts payable, trade							63					63
Other current liabilities							131					131
Other current liabilities							194					194
Long-term liabilities							32					32
Current liabilities							$ 226					226
Crestview Aerospace and TCS [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of businesses	42		2	4	48						42	0	0
Gain on sale of businesses, after tax	$ 19		$ 2	$ 4	$ 25
Net sales											64	119	166
NSS [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of discontinued operations		$ 547
NSS [Member] | Discontinued Operations [Member] | CACI International Inc [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of discontinued operations		$ 547
Vertex Aerospace and NSS [Member] | Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of businesses											234	0	64
Discontinued Operations [Abstract]
Net sales											597	1,429	1,402
Operating costs and expenses (1)											(561)	(1,531)	(1,357)
Operating (loss) income from discontinued operations											36	(102)	45
Interest expense allocated to discontinued operations											(1)	(2)	(5)
(Loss) income from discontinued operations before income taxes											269	(104)	104
Income tax benefit (expense)											(64)	28	(13)
(Loss) income from discontinued operations net of income taxes											$ 205	$ (76)	$ 91